Reproductive implication of D-aspartic acid in human pre-ovulatory follicular fluid.

BACKGROUND: In the present study, we report that D-aspartic acid (D-Asp) occurs in human ovarian follicular fluid and that a relationship may exist between the concentration of this amino acid and oocyte quality. METHODS: Samples of pre-ovulatory follicle fluid were obtained from 20 patients undergoing an IVF programme. The concentration of D-Asp was measured by using specific high-performance liquid chromatography (HPLC) combined with a d-aspartate oxidase. RESULTS: D-Asp occurs in human follicular fluid at a mean concentration of 14.98 +/- 4.51 nmol/ml. A significant difference in the content of this amino acid in the follicular fluid in relation to patient's age exists. In younger women aged 22-34 years (group A), D-Asp was found at a concentration of 19.11 +/- 1.91 nmol/ml, whereas in patients aged 35-40 years (group B), it decreased to 10.86 +/- 1.22 nmol/ml (P < 0.01). In addition, this amino acid was linked to oocyte quality; a relationship exists between D-Asp follicular concentration and the percentage of good quality metaphase II oocytes (P < 0.01), as well as the fertilization rate. CONCLUSIONS: In human follicular fluid, D-Asp is present at a relatively higher concentration in younger women than in older patients and there appears to be a relationship between the concentration of d-Asp and fertility outcome parameters. These findings suggest that follicular D-Asp concentration may be considered as an alternative or additional biochemical marker for oocyte quality in patients undergoing IVF programmes.

The detection of anti-beta2-glycoprotein I antibodies is associated with increased risk of pregnancy loss in women with threatened abortion in the first trimester.

OBJECTIVE: This study was designed to evaluate whether the detection of serum antiphospholipid autoantibodies may be useful in predicting pregnancy outcome in women with threatened abortion in the first trimester. STUDY DESIGN: A group of 77 pregnant women of between 8 and 12 weeks' gestation with vaginal bleeding was tested for serum antiphospholipid, lupus anticoagulants, anticardiolipin, antinuclear antibodies, and anti-beta2-glycoprotein I antibodies, and was followed up until the spontaneous end of pregnancy. A control group composed of 15 healthy women with uncomplicated gestation was tested contemporarily for the same antibody panel. RESULTS: Of the 77 patients with threatened abortion, 32 (41.5%) progressed to deliver at term and 45 (58.5%) experienced early pregnancy loss. Among the antibodies evaluated, only anti-beta2-glycoprotein I was significantly more frequent in those women whose pregnancy resulted in spontaneous abortion (22/45, 49%) than in those who progressed to term (6/32, 19%) or in the control group (2/15, 13%; p=0.004). This difference was specific to the IgM isotype (p=0.001). After adjustment by multivariate analysis, the odds ratio for pregnancy loss associated with a positive beta2-glycoprotein I antibody test was 5.18 (p=0.001). CONCLUSION: The detection of anti-beta2-glycoprotein I antibodies is associated with an increased risk of pregnancy loss in women with threatened abortion in the first trimester.

Surgical strategies in cervico-mediastinal goiters.

AIM: We retrospectively studied clinical picture, diagnosis, treatment and complications of patients with cervico-mediastinal goiter who underwent surgery. METHODS: Sixty-three patients underwent surgical treatment for cervico-mediastinal goiter in the last 10 years. Thirty-two patients (50.8%) had cervico-mediastinal goiter, 24 patients (33.3%) had mediastino-cervical goiter and 7 patients (11.1%) had mediastinal goiter. Forty-seven cases were prevascular goiters and 16 were retrovascular goiters. We performed total thyroidectomy in 25 patients, subtotal thyroidectomy in 31 patients and in 7 cases the resection of residual goiter. In 50 patients we used a cervical approach, in 12 patients the cervical incision was combined with median sternotomy (6 in total) and in 1 patient with transverse sternotomy. RESULTS: Three patients (4.7%) died in the postoperative period (2 cardio-respiratory failure and 1 pulmonary embolism). The histologic study revelead 5 (7.9%) carcinomas. Postoperative complications were: dyspnea in 7 cases (11.1%), transient vocal cord paralysis in 5 patients (7.9%), temporary hypoparathyroidism in 6 patients (9.5%) and kidney failure in 1 case (1.6%). CONCLUSIONS: Cervicotomy is the approach of choice but in some limited cases (carcinoma, thyroiditis, retrovascular goiter, ectopic goiter) the sternotomy should be performed. Postoperative mortality and morbidity is very low, independent of surgical techniques.

Cervical ripening and induction of labor by prostaglandin E2: a comparison between intracervical gel and vaginal pessary.

OBJECTIVE: To compare the effectiveness and safety of two formulations of prostaglandin (PG) E2 (gel and pessary) for induction of labor. Primary outcomes were cervical ripening, initiation/duration of labor, and type of delivery. STUDY DESIGN: A total of 115 women with singleton gestations were consecutively enrolled and assigned to receive intracervical PGE2 (dinoprostone 0.5 mg) by gel (n = 66) or PGE2 (dinoprostone 10 mg) by intravaginal pessary (n = 49). RESULTS: Independently from parity, the vaginal pessary induced successful cervical ripening with a slightly higher but not statistically significant occurrence of vaginal delivery with respect to gel induction. The mean time interval from induction to vaginal delivery did not differ between groups, despite being shorter for the pessary group in inducation-delivery intervals > 12 h. No significant differences were found between the groups with respect to patients who required a second course of PGE2 (9% vs. 2%), as well as oxytocin (11% vs. 13%) induction. No significant difference was found in the incidence of uterine hyperstimulation and other adverse reactions in nulliparas, or in fetal and neonatal outcome. CONCLUSION: Independently from parity, both PGE2 administration routes appeared to be effective in achieving cervical ripening, initiation of labor and optimal type of delivery, and showed the same incidence of side-effects.

Ovarian hyperstimulation-like syndrome after administration of triptorelin to a woman with endometriosis.

Ovarian hyperstimulation after a single dose of gonadotropin-releasing hormone (GnRH) analog is a rare phenomenon. A case of ovarian hyperstimulation-like syndrome after sole administration of triptorelin (Decapeptyl 3.75 mg) is reported in a woman who had undergone surgery for an endometriotic cyst. After administration of the drug, abdominal pressure increased with nausea and diffuse pelvic pain. Ultrasound examination showed bilateral enlargement of the ovaries (right 74 x 62 mm, left 62 x 53 mm), more than 10 follicles ranging in diameter from 15-25 mm, proliferative endometrium 7 mm thick and fluid in the Douglas pouch up to 25 x 23 mm thick. Estradiol plasma level was in the normal range. The syndrome spontaneously resolved in the course of treatment and a spontaneous pregnancy occurred when the triptorelin effect disappeared.

Plasma L-arginine is markedly reduced in pregnant women affected by preeclampsia.

The objective of this study was to determine the concentration of free L-amino acids and in particular of L-arginine in the plasma of pregnant women affected by preeclampsia compared to healthy pregnant women in order to know if an alteration in the concentrations of these amino acids occurs in preeclamspia. Twelve pregnant women affected by preeclampsia and twelve pregnant control women, ages 28-35 years old and at the 35-36 weeks of pregnancy were studied. The blood analysis of free amino acids was carried out by using a high performance liquid chromatographic (HPLC) fluorometric method and OPA-NAC as derivatizing agent for the amino acid determination. In the blood of women affected by preeclampsia L-arginine is markedly reduced compared to controls (about five-fold lower, P<0.01). The other amino acids also are significantly reduced, but to lesser extents (about 1.5 times lower, P<0.05). Thus, the determination of L-arginine in the blood of pregnant women could potentially constitute an additional marker for the early diagnosis of preeclampsia.

[Role of the surgeon in the treatment of small cell lung carcinoma]. / Ruolo del hcirurgo nel trattamento del carcinoma polmonare a piccole cellule.

Surgery has never played a precise and well consolidated role in the planned treatment of lung microcytoma (SCLC). The acknowledged therapeutic strategy associates local treatment (radiotherapy) with general treatment (chemotherapy). Exeresis is particularly indicated in limited or peripheral forms, followed by intensive polychemotherapy. Scintigraphy with octreotide may be used for the initial screening of patients with widespread disease. Another minor role played by surgery is in the treatment of neoplastic foci remaining after chemotherapy. In some cases the use of a radioguided method which, after intravenous injection of radiolabeled octreotide, allows the accumulation of somatostatin analog in neoplastic foci to be assayed intraoperatively using a manual probe, might help the surgeon to check the radical nature of the operation. In addition, octreotide can be used as a radiotherapeutic pharmacological agent or to enhance the efficacy of chemotherapy in microcytoma and other lung tumours with neuroendocrine differentiation.

The role of D-aspartic acid and N-methyl-D-aspartic acid in the regulation of prolactin release.

In this study, using an enzymatic HPLC method in combination with D-aspartate oxidase, we show that N-methyl-D-aspartate (NMDA) is present at nanomolar levels in rat nervous system and endocrine glands as a natural compound, and it is biosynthesized in vivo and in vitro. D-aspartate (D-Asp) is its natural precursor and also occurs as an endogenous compound. Among the endocrine glands, the highest quantities of D-Asp (78 +/- 12 nmol/g) and NMDA (8.4 +/- 1.2 nmol/g) occur in the adenohypophysis, whereas the hypothalamus represents the area of the nervous system where these amino acids are most abundant (55 +/- 9 and 5.6 +/- 1.1 nmol/g for D-Asp and NMDA, respectively). When D-Asp is administered to rats by ip injection, there is a significant uptake of D-Asp into the adenohypophysis and a significant increase in the concentration of NMDA in the adenohypophysis, hypothalamus and hippocampus, suggesting that D-Asp is an endogenous precursor for NMDA biosynthesis. Experiments conducted on tissue homogenates confirm that D-Asp is the precursor of the NMDA and that the enzyme catalyzing this reaction is a methyltransferase. S-adenosyl-L-methionine (SAM) is the methyl group donor. In vivo experiments consisting of ip injections of sodium D-aspartate show that this amino acid induced a significant serum PRL elevation and this effect is dose and time dependent. In vitro experiments conducted on isolated adenohypophysis or adenohypophysis coincubated with the hypothalamus, showed that the release of PRL is caused by a direct action of D-Asp on the pituitary gland and also mediated by the indirect action of NMDA on the hypothalamus. Then, the latter induces the release of a putative factor that in turn stimulates the adenohypophysis reinforcing the PRL release. In conclusion, our data suggest that D-Asp and NMDA are present endogenously in the rat and are involved in the modulation of PRL release.

Secretion of D-aspartic acid by the rat testis and its role in endocrinology of the testis and spermatogenesis.

The D-isomer of aspartic acid (D-Asp) has been found in rat testes. In the present study, samples of testicular venous blood plasma, rete testis fluid, interstitial extracellular fluid, luminal fluid from the seminiferous tubules, testicular parenchymal cells, epididymal spermatozoa and peripheral blood plasma were collected and analyzed for D-Asp by two methods, an enzymatic and a chromatographic HPLC method. The two methods gave very similar results for all samples. The highest concentrations of D-Asp (about 120 nmol/ml) were found in testicular venous blood plasma, with slightly lower concentrations in rete testis fluid (95 nmol/ml) and epididymal spermatozoa (80 nmol/g wet weight). Lower levels were found in testicular parenchymal cells (which would comprise mostly spermatids and spermatocytes), luminal fluid from the seminiferous tubules and interstitial extracellular fluid (26, 23 and 11 nmol/ml respectively). However, these values were all higher than those for peripheral blood plasma (6 nmol/ml). It would appear that D-Asp is being secreted by the testis mostly into the venous blood, passing thence into the rete testis fluid and being incorporated into the spermatozoa at the time or after they leave the testis. The distribution of D-Asp is thus quite different from that of testosterone, and its role and the reason for its high concentration in the male reproductive tract remain to be elucidated.

Properties of the flavoenzyme D-aspartate oxidase from Octopus vulgaris.

The properties of D-aspartate oxidase from Octopus vulgaris (EC 1.4.3.1) have been investigated. The protein is a monomer of M(r) 37,000 containing one mol flavin/mol protein. The enzyme as isolated exists at least in two forms, one containing FAD and the other, which is catalytically inactive, probably containing 6-OH-FAD, as inferred from the absorption spectrum of the enzyme. An additional form of the enzyme, as far as the nature of the coenzyme is concerned, has been detected in the purified enzyme and shown to derive from the form originally containing FAD. The modulation of the coenzyme reactivity exerted by Octopus D-aspartate oxidase, as studied by spectrophotometric techniques, conforms to the one expected for an enzyme belonging to the oxidase class of flavoproteins. Structural investigations show similarities in both the amino-acid composition and the N-terminal amino-acid sequence to bovine D-aspartate oxidase and porcine D-amino-acid oxidase. In summary, the general properties of the enzyme from Octopus vulgaris closely resemble those of the enzyme from beef kidney. Moreover, kinetic analyses suggest that two active-site residues with pKa of 7.1 and 9.1 are critical for catalysis, and that the ionization of such residues has different effects on the catalytic activity depending whether mono- or dicarboxylic D-amino acids are used as substrate.

Biological role of D-amino acid oxidase and D-aspartate oxidase. Effects of D-amino acids.

D-Amino acids administered to animals are absorbed by the intestine and transported through the blood-stream to solid tissues where they are oxidized in vivo by D-amino acid oxidase and D-aspartate oxidase to produce the same compounds they do in vitro; i.e. NH3, H2O2, and the keto acid corresponding to the amino acid ingested. In the liver and kidneys of the animals, an inverse relationship exists between the occurrence of D-amino acids and these oxidative enzymes. For example, younger animals have lower amounts of these oxidases and consequently higher concentrations of free D-amino acids compared to adult animals. If the ingested D-amino acids are not metabolized by these enzymes, they will accumulate in the tissues and may provoke serious damage, e.g. suppression of the synthesis of other essential enzymes and inhibition of the growth rate of the animals. A specific enzyme induction for these D-amino acid oxidases exists in young rats following ingestion of free D-amino acids by the mother. Specifically, when a mother rat ingests D-Ala or D-Asp during pregnancy and suckling, an increase in D-amino acid oxidase or D-aspartate oxidase is observed in the liver and kidneys of the baby rats. These results suggest that the in vivo biological role of these oxidases in animals is to act as detoxifying agents to metabolize D-amino acids which may have accumulated during aging.